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Lamptey H, Newcomb B, Bonney EY, Aboagye JO, Puplampu P, Ganu VJ, Ansa G, Oliver-Commey J, Kyei GB. Healthcare Provider Perspectives on HIV Cure Research in Ghana. AIDS Res Treat 2023; 2023:8158439. [PMID: 37292229 PMCID: PMC10247315 DOI: 10.1155/2023/8158439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 05/15/2023] [Accepted: 05/17/2023] [Indexed: 06/10/2023] Open
Abstract
Introduction Antiretroviral therapy (ART) has reduced mortality and improved life expectancy among HIV patients but does not provide a cure. Patients must remain on lifelong medications and deal with drug resistance and side effects. This underscores the need for HIV cure research. However, participation in HIV cure research has risks without guaranteed benefits. We determined what HIV healthcare providers know about HIV cure research trials, the risks involved, and what kind of cure interventions they are likely to recommend for their patients. Methods We conducted in-depth qualitative interviews with 39 HIV care providers consisting of 12 physicians, 8 counsellors, 14 nurses, 2 pharmacists, 2 laboratory scientists, and 1 community advocate from three hospitals. Interviews were transcribed verbatim and coded, and thematic analysis was performed independently by two investigators. Results Participants were happy about the success of current treatments and hopeful that an HIV cure will be found in the near future, just as ART was discovered through research. They described cure as total eradication of the virus from the body and inability to test positive for HIV or transmit the virus. In terms of risk tolerance, respondents would recommend to their patients' studies with mild to moderate risks like what patients on antiretroviral therapy experience. Participants were reluctant to recommend treatment interruption to patients as part of a cure study and wished trials could be performed without stopping treatment. Healthcare providers categorically rejected death or permanent disability as an acceptable risk. The possibility of finding a cure that will benefit the individual or future generations was strong motivations for providers to recommend cure trials to their patients, as was transparency and adequate information on proposed trials. Overall, the participants were not actively seeking knowledge on cure research and lacked information on the various cure modalities under investigation. Conclusion While hopeful for an HIV cure, healthcare providers in Ghana expect a cure to be definitive and pose minimal risk to their patients.
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Affiliation(s)
- Helena Lamptey
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Benjamin Newcomb
- Departments of Medicine and Molecular Microbiology, Washington University School of Medicine in St. Louis, 660 S. Euclid Ave, St. Louis, MO, USA
| | - Evelyn Y. Bonney
- Department of Virology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Accra, Ghana
| | - James O. Aboagye
- Department of Virology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Peter Puplampu
- Department of Medicine, University of Ghana Medical School, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Vincent J. Ganu
- Department of Medicine, University of Ghana Medical School, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Gloria Ansa
- Department of Public Health, University of Ghana Hospital, Legon, Accra, Ghana
| | | | - George B. Kyei
- Departments of Medicine and Molecular Microbiology, Washington University School of Medicine in St. Louis, 660 S. Euclid Ave, St. Louis, MO, USA
- Department of Virology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Accra, Ghana
- Medical and Scientific Research Center, University of Ghana Medical Centre, Accra, Ghana
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2
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Mohammed S, Shamseddine AA, Newcomb B, Chavez RS, Panzner TD, Lee AH, Canals D, Okeoma CM, Clarke CJ, Hannun YA. Sublethal doxorubicin promotes migration and invasion of breast cancer cells: role of Src Family non-receptor tyrosine kinases. Breast Cancer Res 2021; 23:76. [PMID: 34315513 PMCID: PMC8317414 DOI: 10.1186/s13058-021-01452-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 07/01/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Doxorubicin (Dox) is a widely used chemotherapy, but its effectiveness is limited by dose-dependent side effects. Although lower Dox doses reduce this risk, studies have reported higher recurrence of local disease with no improvement in survival rate in patients receiving low doses of Dox. To effectively mitigate this, a better understanding of the adverse effects of suboptimal Dox doses is needed. METHODS Effects of sublethal dose of Dox on phenotypic changes were assessed with light and confocal microscopy. Migratory and invasive behavior were assessed by wound healing and transwell migration assays. MTT and LDH release assays were used to analyze cell growth and cytotoxicity. Flow cytometry was employed to detect cell surface markers of cancer stem cell population. Expression and activity of matrix metalloproteinases were probed with qRT-PCR and zymogen assay. To identify pathways affected by sublethal dose of Dox, exploratory RNAseq was performed and results were verified by qRT-PCR in multiple cell lines (MCF7, ZR75-1 and U-2OS). Regulation of Src Family kinases (SFK) by key players in DNA damage response was assessed by siRNA knockdown along with western blot and qRT-PCR. Dasatinib and siRNA for Fyn and Yes was employed to inhibit SFKs and verify their role in increased migration and invasion in MCF7 cells treated with sublethal doses of Dox. RESULTS The results show that sublethal Dox treatment leads to increased migration and invasion in otherwise non-invasive MCF7 breast cancer cells. Mechanistically, these effects were independent of the epithelial mesenchymal transition, were not due to increased cancer stem cell population, and were not observed with other chemotherapies. Instead, sublethal Dox induces expression of multiple SFK-including Fyn, Yes, and Src-partly in a p53 and ATR-dependent manner. These effects were validated in multiple cell lines. Functionally, inhibiting SFKs with Dasatinib and specific downregulation of Fyn suppressed Dox-induced migration and invasion of MCF7 cells. CONCLUSIONS Overall, this study demonstrates that sublethal doses of Dox activate a pro-invasive, pro-migration program in cancer cells. Furthermore, by identifying SFKs as key mediators of these effects, our results define a potential therapeutic strategy to mitigate local invasion through co-treatment with Dasatinib.
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Affiliation(s)
- Samia Mohammed
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, 11794- 8430, USA.,Stony Brook University Cancer Center, MART Level 9, Stony Brook University, Stony Brook, NY, 11794-8430, USA.,Department of Medicine, Stony Brook University, Health Science Center, Hospital Pavilion Level 5, Stony Brook, NY, 11794-8430, USA
| | - Achraf A Shamseddine
- Department of Medicine, Stony Brook University, Health Science Center, Hospital Pavilion Level 5, Stony Brook, NY, 11794-8430, USA
| | - Benjamin Newcomb
- Department of Medicine, Stony Brook University, Health Science Center, Hospital Pavilion Level 5, Stony Brook, NY, 11794-8430, USA
| | - Ronald S Chavez
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, 11794- 8430, USA
| | - Tyler D Panzner
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY, 11794-8430, USA
| | - Allen H Lee
- Stony Brook University Cancer Center, MART Level 9, Stony Brook University, Stony Brook, NY, 11794-8430, USA.,Department of Medicine, Stony Brook University, Health Science Center, Hospital Pavilion Level 5, Stony Brook, NY, 11794-8430, USA.,Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY, 11794-8430, USA
| | - Daniel Canals
- Stony Brook University Cancer Center, MART Level 9, Stony Brook University, Stony Brook, NY, 11794-8430, USA.,Department of Medicine, Stony Brook University, Health Science Center, Hospital Pavilion Level 5, Stony Brook, NY, 11794-8430, USA
| | - Chioma M Okeoma
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY, 11794-8430, USA
| | - Christopher J Clarke
- Stony Brook University Cancer Center, MART Level 9, Stony Brook University, Stony Brook, NY, 11794-8430, USA. .,Department of Medicine, Stony Brook University, Health Science Center, Hospital Pavilion Level 5, Stony Brook, NY, 11794-8430, USA.
| | - Yusuf A Hannun
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, 11794- 8430, USA. .,Stony Brook University Cancer Center, MART Level 9, Stony Brook University, Stony Brook, NY, 11794-8430, USA. .,Department of Medicine, Stony Brook University, Health Science Center, Hospital Pavilion Level 5, Stony Brook, NY, 11794-8430, USA. .,Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY, 11794-8430, USA. .,The Northport Veterans Affairs Hospital, Northport, NY, 11768, USA.
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3
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Alsamman S, Christenson SA, Yu A, Ayad NME, Mooring MS, Segal JM, Hu JKH, Schaub JR, Ho SS, Rao V, Marlow MM, Turner SM, Sedki M, Pantano L, Ghoshal S, Ferreira DDS, Ma HY, Duwaerts CC, Espanol-Suner R, Wei L, Newcomb B, Mileva I, Canals D, Hannun YA, Chung RT, Mattis AN, Fuchs BC, Tager AM, Yimlamai D, Weaver VM, Mullen AC, Sheppard D, Chen JY. Targeting acid ceramidase inhibits YAP/TAZ signaling to reduce fibrosis in mice. Sci Transl Med 2021; 12:12/557/eaay8798. [PMID: 32817366 DOI: 10.1126/scitranslmed.aay8798] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 02/11/2020] [Accepted: 06/30/2020] [Indexed: 12/11/2022]
Abstract
Hepatic stellate cells (HSCs) drive hepatic fibrosis. Therapies that inactivate HSCs have clinical potential as antifibrotic agents. We previously identified acid ceramidase (aCDase) as an antifibrotic target. We showed that tricyclic antidepressants (TCAs) reduce hepatic fibrosis by inhibiting aCDase and increasing the bioactive sphingolipid ceramide. We now demonstrate that targeting aCDase inhibits YAP/TAZ activity by potentiating its phosphorylation-mediated proteasomal degradation via the ubiquitin ligase adaptor protein β-TrCP. In mouse models of fibrosis, pharmacologic inhibition of aCDase or genetic knockout of aCDase in HSCs reduces fibrosis, stromal stiffness, and YAP/TAZ activity. In patients with advanced fibrosis, aCDase expression in HSCs is increased. Consistently, a signature of the genes most down-regulated by ceramide identifies patients with advanced fibrosis who could benefit from aCDase targeting. The findings implicate ceramide as a critical regulator of YAP/TAZ signaling and HSC activation and highlight aCDase as a therapeutic target for the treatment of fibrosis.
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Affiliation(s)
- Sarah Alsamman
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94115, USA
| | - Stephanie A Christenson
- Division of Pulmonary, Critical Care, Allergy and Sleep, Department of Medicine, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Amy Yu
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94115, USA
| | - Nadia M E Ayad
- Center for Bioengineering and Tissue Regeneration, Department of Surgery, University of California, San Francisco, San Francisco, CA 94143, USA.,UC Berkeley-UCSF Graduate Program in Bioengineering, San Francisco, CA 94143, USA
| | - Meghan S Mooring
- Division of Pediatric Gastroenterology and Hepatology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Joe M Segal
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94115, USA
| | - Jimmy Kuang-Hsien Hu
- Division of Oral Biology & Medicine, School of Dentistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | | | - Steve S Ho
- Pliant Therapeutics, South San Francisco, CA 94080, USA
| | - Vikram Rao
- Pliant Therapeutics, South San Francisco, CA 94080, USA
| | | | | | - Mai Sedki
- Internal Medicine, Kaiser Permanente, San Francisco, CA 94115, USA
| | - Lorena Pantano
- Department of Biostatistics, Harvard School of Public Health, Boston, MA 02115, USA
| | - Sarani Ghoshal
- Division of Surgical Oncology, Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA 02114, USA
| | - Diego Dos Santos Ferreira
- Athinoula A. Martinos Center for Biomedical Imaging, Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Hsiao-Yen Ma
- Lung Biology Center, Department of Medicine, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Caroline C Duwaerts
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94115, USA.,Liver Center, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Regina Espanol-Suner
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Lan Wei
- Division of Surgical Oncology, Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA 02114, USA
| | - Benjamin Newcomb
- Departments of Medicine and Biochemistry and Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY 11794, USA
| | - Izolda Mileva
- Departments of Medicine and Biochemistry and Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY 11794, USA
| | - Daniel Canals
- Departments of Medicine and Biochemistry and Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY 11794, USA
| | - Yusuf A Hannun
- Departments of Medicine and Biochemistry and Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY 11794, USA
| | - Raymond T Chung
- Liver Center, Division of Gastroenterology, Department of Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Aras N Mattis
- Liver Center, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA.,Department of Pathology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Bryan C Fuchs
- Division of Surgical Oncology, Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA 02114, USA
| | - Andrew M Tager
- Division of Pulmonary and Critical Care Medicine, Fibrosis Research Center, and Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Dean Yimlamai
- Division of Pediatric Gastroenterology and Hepatology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Valerie M Weaver
- Center for Bioengineering and Tissue Regeneration, Department of Surgery, University of California, San Francisco, San Francisco, CA 94143, USA.,UC Berkeley-UCSF Graduate Program in Bioengineering, San Francisco, CA 94143, USA.,Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA 94143, USA.,Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94158, USA.,Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA 94158, USA.,Department of Radiation Oncology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Alan C Mullen
- Liver Center, Division of Gastroenterology, Department of Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Dean Sheppard
- Division of Pulmonary, Critical Care, Allergy and Sleep, Department of Medicine, University of California, San Francisco, San Francisco, CA 94158, USA. .,Lung Biology Center, Department of Medicine, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Jennifer Y Chen
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94115, USA. .,Liver Center, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
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4
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Newcomb B, Rhein C, Mileva I, Ahmad R, Clarke CJ, Snider J, Obeid LM, Hannun YA. Identification of an acid sphingomyelinase ceramide kinase pathway in the regulation of the chemokine CCL5. J Lipid Res 2018; 59:1219-1229. [PMID: 29724781 DOI: 10.1194/jlr.m084202] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 04/25/2018] [Indexed: 02/01/2023] Open
Abstract
Acid sphingomyelinase (ASM) hydrolyzes sphingomyelin to produce the biologically active lipid ceramide. Previous studies have implicated ASM in the induction of the chemokine CCL5 in response to TNF-α however, the lipid mediator of this effect was not established. In the present study, we identified a novel pathway connecting ASM and ceramide kinase (CERK). The results show that TNF-α induces the formation of ceramide 1-phosphate (C-1-P) in a CERK-dependent manner. Silencing of CERK blocks CCL5 production in response to TNF-α. Interestingly, cells lacking ASM have decreased C-1-P production following TNF-α treatment, suggesting that ASM may be acting upstream of CERK. Functionally, ASM and CERK induce a highly concordant program of cytokine production and both are required for migration of breast cancer cells. Taken together, these data suggest ASM can produce ceramide which is then converted to C-1-P by CERK, and that C-1-P is required for production of CCL5 and several cytokines and chemokines, with roles in cell migration. These results highlight the diversity in action of ASM through more than one bioactive sphingolipid.
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Affiliation(s)
- Benjamin Newcomb
- Stony Brook Cancer Center Stony Brook University, Stony Brook, NY 11794
| | - Cosima Rhein
- Stony Brook Cancer Center Stony Brook University, Stony Brook, NY 11794.,Department of Psychiatry and Psychotherapy, University Hospital, Friedrich-Alexander University Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
| | - Izolda Mileva
- Stony Brook Cancer Center Stony Brook University, Stony Brook, NY 11794
| | - Rasheed Ahmad
- Immunology and Innovative Cell Therapy Unit, Dasman Diabetes Institute, Kuwait City, Kuwait
| | | | - Justin Snider
- Stony Brook Cancer Center Stony Brook University, Stony Brook, NY 11794
| | - Lina M Obeid
- Stony Brook Cancer Center Stony Brook University, Stony Brook, NY 11794.,Department of Medicine, Stony Brook University, Stony Brook, NY 11794
| | - Yusuf A Hannun
- Stony Brook Cancer Center Stony Brook University, Stony Brook, NY 11794 .,Department of Medicine, Stony Brook University, Stony Brook, NY 11794
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5
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Chen JY, Newcomb B, Zhou C, Pondick JV, Ghoshal S, York SR, Motola DL, Coant N, Yi JK, Mao C, Tanabe KK, Bronova I, Berdyshev EV, Fuchs BC, Hannun Y, Chung RT, Mullen AC. Tricyclic Antidepressants Promote Ceramide Accumulation to Regulate Collagen Production in Human Hepatic Stellate Cells. Sci Rep 2017; 7:44867. [PMID: 28322247 PMCID: PMC5359599 DOI: 10.1038/srep44867] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 02/15/2017] [Indexed: 12/21/2022] Open
Abstract
Activation of hepatic stellate cells (HSCs) in response to injury is a key step in hepatic fibrosis, and is characterized by trans-differentiation of quiescent HSCs to HSC myofibroblasts, which secrete extracellular matrix proteins responsible for the fibrotic scar. There are currently no therapies to directly inhibit hepatic fibrosis. We developed a small molecule screen to identify compounds that inactivate human HSC myofibroblasts through the quantification of lipid droplets. We screened 1600 compounds and identified 21 small molecules that induce HSC inactivation. Four hits were tricyclic antidepressants (TCAs), and they repressed expression of pro-fibrotic factors Alpha-Actin-2 (ACTA2) and Alpha-1 Type I Collagen (COL1A1) in HSCs. RNA sequencing implicated the sphingolipid pathway as a target of the TCAs. Indeed, TCA treatment of HSCs promoted accumulation of ceramide through inhibition of acid ceramidase (aCDase). Depletion of aCDase also promoted accumulation of ceramide and was associated with reduced COL1A1 expression. Treatment with B13, an inhibitor of aCDase, reproduced the antifibrotic phenotype as did the addition of exogenous ceramide. Our results show that detection of lipid droplets provides a robust readout to screen for regulators of hepatic fibrosis and have identified a novel antifibrotic role for ceramide.
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Affiliation(s)
- Jennifer Y Chen
- Gastrointestinal Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Benjamin Newcomb
- Health Science Center, Stony Brook University, Stony Brook, NY USA
| | - Chan Zhou
- Gastrointestinal Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Joshua V Pondick
- Gastrointestinal Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Sarani Ghoshal
- Division of Surgical Oncology, Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA USA
| | - Samuel R York
- Gastrointestinal Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Daniel L Motola
- Gastrointestinal Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Nicolas Coant
- Health Science Center, Stony Brook University, Stony Brook, NY USA
| | - Jae Kyo Yi
- Health Science Center, Stony Brook University, Stony Brook, NY USA
| | - Cungui Mao
- Health Science Center, Stony Brook University, Stony Brook, NY USA
| | - Kenneth K Tanabe
- Division of Surgical Oncology, Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA USA
| | | | | | - Bryan C Fuchs
- Division of Surgical Oncology, Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA USA
| | - Yusuf Hannun
- Health Science Center, Stony Brook University, Stony Brook, NY USA
| | - Raymond T Chung
- Gastrointestinal Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Alan C Mullen
- Gastrointestinal Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA.,Harvard Stem Cell Institute, Cambridge, MA 02138 USA
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6
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Hannun YA, Newcomb B. A new twist to the emerging functions of ceramides in cancer: novel role for platelet acid sphingomyelinase in cancer metastasis. EMBO Mol Med 2016; 7:692-4. [PMID: 25859016 PMCID: PMC4459812 DOI: 10.15252/emmm.201505161] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
It is now appreciated that sphingolipids constitute a rich class of bioactive molecules that include ceramide, sphingosine, and sphingosine 1‐phosphate whose formation is controlled by a network of highly regulated enzymes (Hannun & Obeid, 2008). Notably, several stress stimuli induce the production of ceramide, which, as a single entity, has been traditionally associated with apoptotic and growth suppressive functions. However, recent data clearly suggest that this simplistic formulation is no longer tenable.
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Affiliation(s)
- Yusuf A Hannun
- Department of Medicine, The Stony Brook Cancer Center, Stony Brook, NY, USA
| | - Benjamin Newcomb
- Department of Medicine, The Stony Brook Cancer Center, Stony Brook, NY, USA
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7
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Bai A, Szulc ZM, Bielawski J, Pierce JS, Rembiesa B, Terzieva S, Mao C, Xu R, Wu B, Clarke CJ, Newcomb B, Liu X, Norris J, Hannun YA, Bielawska A. Targeting (cellular) lysosomal acid ceramidase by B13: design, synthesis and evaluation of novel DMG-B13 ester prodrugs. Bioorg Med Chem 2014; 22:6933-44. [PMID: 25456083 DOI: 10.1016/j.bmc.2014.10.025] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 10/06/2014] [Accepted: 10/15/2014] [Indexed: 11/29/2022]
Abstract
Acid ceramidase (ACDase) is being recognized as a therapeutic target for cancer. B13 represents a moderate inhibitor of ACDase. The present study concentrates on the lysosomal targeting of B13 via its N,N-dimethylglycine (DMG) esters (DMG-B13 prodrugs). Novel analogs, the isomeric mono-DMG-B13, LCL522 (3-O-DMG-B13·HCl) and LCL596 (1-O-DMG-B13·HCl) and di-DMG-B13, LCL521 (1,3-O, O-DMG-B13·2HCl) conjugates, were designed and synthesized through N,N-dimethyl glycine (DMG) esterification of the hydroxyl groups of B13. In MCF7 cells, DMG-B13 prodrugs were efficiently metabolized to B13. The early inhibitory effect of DMG-B13 prodrugs on cellular ceramidases was ACDase specific by their lysosomal targeting. The corresponding dramatic decrease of cellular Sph (80-97% Control/1h) by DMG-B13 prodrugs was mainly from the inhibition of the lysosomal ACDase.
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Affiliation(s)
- Aiping Bai
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA; Lipidomics Facility, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Zdzislaw M Szulc
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA; Lipidomics Facility, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Jacek Bielawski
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA; Lipidomics Facility, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Jason S Pierce
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA; Lipidomics Facility, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Barbara Rembiesa
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA; Lipidomics Facility, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Silva Terzieva
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA; Lipidomics Facility, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Cungui Mao
- Department of Medicine and the Stony Brook Cancer Center at Stony Brook University, Stony Brook, NY 11794, USA
| | - Ruijuan Xu
- Department of Medicine and the Stony Brook Cancer Center at Stony Brook University, Stony Brook, NY 11794, USA
| | - Bill Wu
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Christopher J Clarke
- Department of Medicine and the Stony Brook Cancer Center at Stony Brook University, Stony Brook, NY 11794, USA
| | - Benjamin Newcomb
- Department of Medicine and the Stony Brook Cancer Center at Stony Brook University, Stony Brook, NY 11794, USA
| | - Xiang Liu
- Department of Microbiology and Immunology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - James Norris
- Department of Microbiology and Immunology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA
| | - Yusuf A Hannun
- Department of Medicine and the Stony Brook Cancer Center at Stony Brook University, Stony Brook, NY 11794, USA.
| | - Alicja Bielawska
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA; Lipidomics Facility, Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425, USA.
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8
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Perry DM, Newcomb B, Adada M, Wu BX, Roddy P, Kitatani K, Siskind L, Obeid LM, Hannun YA. Defining a role for acid sphingomyelinase in the p38/interleukin-6 pathway. J Biol Chem 2014; 289:22401-12. [PMID: 24951586 DOI: 10.1074/jbc.m114.589648] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Acid sphingomyelinase (ASM) is one of the key enzymes involved in regulating the metabolism of the bioactive sphingolipid ceramide in the sphingolipid salvage pathway, yet defining signaling pathways by which ASM exerts its effects has proven difficult. Previous literature has implicated sphingolipids in the regulation of cytokines such as interleukin-6 (IL-6), but the specific sphingolipid pathways and mechanisms involved in inflammatory signaling need to be further elucidated. In this work, we sought to define the role of ASM in IL-6 production because our previous work showed that a parallel pathway of ceramide metabolism, acid β-glucosidase 1, negatively regulates IL-6. First, silencing ASM with siRNA abrogated IL-6 production in response to the tumor promoter, 4β-phorbol 12-myristate 13-acetate (PMA), in MCF-7 cells, in distinction to acid β-glucosidase 1 and acid ceramidase, suggesting specialization of the pathways. Moreover, treating cells with siRNA to ASM or with the indirect pharmacologic inhibitor desipramine resulted in significant inhibition of TNFα- and PMA-induced IL-6 production in MDA-MB-231 and HeLa cells. Knockdown of ASM was found to significantly inhibit PMA-dependent IL-6 induction at the mRNA level, probably ruling out mechanisms of translation or secretion of IL-6. Further, ASM knockdown or desipramine blunted p38 MAPK activation in response to TNFα, revealing a key role for ASM in activating p38, a signaling pathway known to regulate IL-6 induction. Last, knockdown of ASM dramatically blunted invasion of HeLa and MDA-MB-231 cells through Matrigel. Taken together, these results demonstrate that ASM plays a critical role in p38 signaling and IL-6 synthesis with implications for tumor pathobiology.
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Affiliation(s)
- David M Perry
- From the Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | | | | | - Bill X Wu
- From the Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Patrick Roddy
- From the Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Kazuyuki Kitatani
- the Tohoku Medical Megabank Organization and Department of Obstetrics and Gynecology, Tohoku University Graduate School of Medicine, Sendai 980-8575, Japan
| | - Leah Siskind
- the Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202
| | - Lina M Obeid
- the Department of Medicine Stony Brook University, Stony Brook, New York 11794, and the Northport Veterans Affairs Hospital, Northport, New York 11768
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Spincemaille P, Chandhok G, Newcomb B, Verbeek J, Vriens K, Zibert A, Schmidt H, Hannun YA, van Pelt J, Cassiman D, Cammue BPA, Thevissen K. The plant decapeptide OSIP108 prevents copper-induced apoptosis in yeast and human cells. Biochim Biophys Acta 2014; 1843:1207-1215. [PMID: 24632503 DOI: 10.1016/j.bbamcr.2014.03.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 02/24/2014] [Accepted: 03/04/2014] [Indexed: 02/07/2023]
Abstract
We previously identified the Arabidopsis thaliana-derived decapeptide OSIP108, which increases tolerance of plants and yeast cells to oxidative stress. As excess copper (Cu) is known to induce oxidative stress and apoptosis, and is characteristic for the human pathology Wilson disease, we investigated the effect of OSIP108 on Cu-induced toxicity in yeast. We found that OSIP108 increased yeast viability in the presence of toxic Cu concentrations, and decreased the prevalence of Cu-induced apoptotic markers. Next, we translated these results to the human hepatoma HepG2 cell line, demonstrating anti-apoptotic activity of OSIP108 in this cell line. In addition, we found that OSIP108 did not affect intracellular Cu levels in HepG2 cells, but preserved HepG2 mitochondrial ultrastructure. As Cu is known to induce acid sphingomyelinase activity of HepG2 cells, we performed a sphingolipidomic analysis of OSIP108-treated HepG2 cells. We demonstrated that OSIP108 decreased the levels of several sphingoid bases and ceramide species. Moreover, exogenous addition of the sphingoid base dihydrosphingosine abolished the protective effect of OSIP108 against Cu-induced cell death in yeast. These findings indicate the potential of OSIP108 to prevent Cu-induced apoptosis, possibly via its effects on sphingolipid homeostasis.
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Affiliation(s)
- Pieter Spincemaille
- Centre of Microbial and Plant Genetics (CMPG), KU Leuven, Kasteelpark Arenberg 20, 3001 Heverlee, Belgium
| | - Gursimran Chandhok
- Clinic for Transplantation Medicine, Münster University Hospital, Albert-Schweitzer-Campus 1, Building A14, D-48149 Münster, Germany
| | - Benjamin Newcomb
- Department of Medicine and the Stony Brook Cancer Center, University of Stony Brook, Stony Brook, New York, 11794, USA
| | - Jef Verbeek
- Department of Hepatology and Metabolic Center, University Hospital Gasthuisberg, Herestraat 49, 3000 Leuven, Belgium
| | - Kim Vriens
- Centre of Microbial and Plant Genetics (CMPG), KU Leuven, Kasteelpark Arenberg 20, 3001 Heverlee, Belgium
| | - Andree Zibert
- Clinic for Transplantation Medicine, Münster University Hospital, Albert-Schweitzer-Campus 1, Building A14, D-48149 Münster, Germany
| | - Hartmut Schmidt
- Clinic for Transplantation Medicine, Münster University Hospital, Albert-Schweitzer-Campus 1, Building A14, D-48149 Münster, Germany
| | - Yusuf A Hannun
- Department of Medicine and the Stony Brook Cancer Center, University of Stony Brook, Stony Brook, New York, 11794, USA
| | - Jos van Pelt
- Department of Hepatology and Metabolic Center, University Hospital Gasthuisberg, Herestraat 49, 3000 Leuven, Belgium
| | - David Cassiman
- Department of Hepatology and Metabolic Center, University Hospital Gasthuisberg, Herestraat 49, 3000 Leuven, Belgium
| | - Bruno P A Cammue
- Centre of Microbial and Plant Genetics (CMPG), KU Leuven, Kasteelpark Arenberg 20, 3001 Heverlee, Belgium.,Department of Plant Systems Biology, VIB, Technologiepark 927, 9052, Ghent, Belgium
| | - Karin Thevissen
- Centre of Microbial and Plant Genetics (CMPG), KU Leuven, Kasteelpark Arenberg 20, 3001 Heverlee, Belgium
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Montefusco DJ, Chen L, Matmati N, Lu S, Newcomb B, Cooper GF, Hannun YA, Lu X. Distinct signaling roles of ceramide species in yeast revealed through systematic perturbation and systems biology analyses. Sci Signal 2013; 6:rs14. [PMID: 24170935 PMCID: PMC3974757 DOI: 10.1126/scisignal.2004515] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Ceramide, the central molecule of sphingolipid metabolism, is an important bioactive molecule that participates in various cellular regulatory events and that has been implicated in disease. Deciphering ceramide signaling is challenging because multiple ceramide species exist, and many of them may have distinct functions. We applied systems biology and molecular approaches to perturb ceramide metabolism in the yeast Saccharomyces cerevisiae and inferred causal relationships between ceramide species and their potential targets by combining lipidomic, genomic, and transcriptomic analyses. We found that during heat stress, distinct metabolic mechanisms controlled the abundance of different groups of ceramide species and provided experimental support for the importance of the dihydroceramidase Ydc1 in mediating the decrease in dihydroceramides during heat stress. Additionally, distinct groups of ceramide species, with different N-acyl chains and hydroxylations, regulated different sets of functionally related genes, indicating that the structural complexity of these lipids produces functional diversity. The transcriptional modules that we identified provide a resource to begin to dissect the specific functions of ceramides.
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Affiliation(s)
- David J. Montefusco
- Dept. Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina
| | - Lujia Chen
- Dept. Biomedical Informatics, University of Pittsburgh, Pittsburgh, PA 15232
| | - Nabil Matmati
- Dept. Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina
- Department of Medicine and the Stony Brook Cancer Center at Stony Brook University, Stony Brook, NY, 11794
| | - Songjian Lu
- Dept. Biomedical Informatics, University of Pittsburgh, Pittsburgh, PA 15232
| | - Benjamin Newcomb
- Dept. Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina
- Department of Medicine and the Stony Brook Cancer Center at Stony Brook University, Stony Brook, NY, 11794
| | - Gregory F. Cooper
- Dept. Biomedical Informatics, University of Pittsburgh, Pittsburgh, PA 15232
| | - Yusuf A. Hannun
- Dept. Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina
- Department of Medicine and the Stony Brook Cancer Center at Stony Brook University, Stony Brook, NY, 11794
| | - Xinghua Lu
- Dept. Biomedical Informatics, University of Pittsburgh, Pittsburgh, PA 15232
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Montefusco DJ, Newcomb B, Gandy JL, Brice SE, Matmati N, Cowart LA, Hannun YA. Sphingoid bases and the serine catabolic enzyme CHA1 define a novel feedforward/feedback mechanism in the response to serine availability. J Biol Chem 2012; 287:9280-9. [PMID: 22277656 DOI: 10.1074/jbc.m111.313445] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Targets of bioactive sphingolipids in Saccharomyces cerevisiae were previously identified using microarray experiments focused on sphingolipid-dependent responses to heat stress. One of these heat-induced genes is the serine deamidase/dehydratase Cha1 known to be regulated by increased serine availability. This study investigated the hypothesis that sphingolipids may mediate the induction of Cha1 in response to serine availability. The results showed that inhibition of de novo synthesis of sphingolipids, pharmacologically or genetically, prevented the induction of Cha1 in response to increased serine availability. Additional studies implicated the sphingoid bases phytosphingosine and dihydrosphingosine as the likely mediators of Cha1 up-regulation. The yeast protein kinases Pkh1 and Pkh2, known sphingoid base effectors, were found to mediate CHA1 up-regulation via the transcription factor Cha4. Because the results disclosed a role for sphingolipids in negative feedback regulation of serine metabolism, we investigated the effects of disrupting this mechanism on sphingolipid levels and on cell growth. Intriguingly, exposure of the cha1Δ strain to high serine resulted in hyperaccumulation of endogenous serine and in turn a significant accumulation of sphingoid bases and ceramides. Under these conditions, the cha1Δ strain displayed a significant growth defect that was sphingolipid-dependent. Together, this work reveals a feedforward/feedback loop whereby the sphingoid bases serve as sensors of serine availability and mediate up-regulation of Cha1 in response to serine availability, which in turn regulates sphingolipid levels by limiting serine accumulation.
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Affiliation(s)
- David J Montefusco
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29403, USA
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Thaminy S, Newcomb B, Kim J, Gatbonton T, Foss E, Simon J, Bedalov A. Hst3 Is Regulated by Mec1-dependent Proteolysis and Controls the S Phase Checkpoint and Sister Chromatid Cohesion by Deacetylating Histone H3 at Lysine 56. J Biol Chem 2007; 282:37805-14. [DOI: 10.1074/jbc.m706384200] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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Porco JA, Deegan T, Devonport W, Gooding OW, Heisler K, Labadie JW, Newcomb B, Nguyen C, van Eikeren P, Wong J, Wright P. Automated chemical synthesis: from resins to instruments. Mol Divers 2001; 2:197-206. [PMID: 9249755 DOI: 10.1007/bf01715635] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Solid-phase organic synthesis is now a prevalent activity in drug discovery. In keeping with this keen interest is the need to develop reliable automated synthesis instrumentation as well as polymeric supports and linkers suitable for the full range of organic synthesis applications. In this paper, we review our activities in the development of new and enabling tools for automated chemical synthesis, including the following: (i) new solid supports such as ArgoGel (PS-PEG-based) and Argo-X203 (PS-based); and (ii) the Nautilus 2400 system, a fully closed and inert automated chemistry development workstation. Selected chemistry optimization and synthesis examples performed on the Nautilus and new solid supports will be described.
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Affiliation(s)
- J A Porco
- Argonaut Technologies Inc., San Carlos, CA 94070, USA
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